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arXiv · 2008.12791

Continuous-variable gate teleportation and bosonic-code error correction

Blayney W. Walshe·Ben Q. Baragiola·Rafael N. Alexander·Nicolas C. Menicucci
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Abstract

We examine continuous-variable gate teleportation using entangled states made from pure product states sent through a beamsplitter. We show that such states are Choi states for a (typically) non-unitary gate, and we derive the associated Kraus operator for teleportation, which can be used to realize non-Gaussian, non-unitary quantum operations on an input state. With this result, we show how gate teleportation is used to perform error correction on bosonic qubits encoded using the Gottesman-Kitaev-Preskill code. This result is presented in the context of deterministically produced macronode cluster states, generated by constant-depth linear optical networks, supplemented with a probabilistic supply of GKP states. The upshot of our technique is that state injection for both gate teleportation and error correction can be achieved without active squeezing operations -- an experimental bottleneck for quantum optical implementations.

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Blayney W. Walshe, Ben Q. Baragiola, Rafael N. Alexander, Nicolas C. Menicucci. 2020-08-28. Continuous-variable gate teleportation and bosonic-code error correction. https://doi.org/10.1103/physreva.102.062411

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